Commit work in progress of fixing the implementation of content mixing in Jitsi VideoBridge.

src/org/jitsi/impl/neomedia/device/AbstractMediaDevice.java

@@ -66,16 +66,59 @@ public void connect(DataSource captureDevice)
      */
     protected abstract DataSource createOutputDataSource();
 
+    /**
+     * Initializes a new <tt>Processor</tt> instance which is to be used to play
+     * back media on this <tt>MediaDevice</tt>. Allows extenders to, for
+     * example, disable the playback on this <tt>MediaDevice</tt> by completely
+     * overriding and returning <tt>null</tt>.
+     *
+     * @param dataSource the <tt>DataSource</tt> which is to be played back by
+     * the new <tt>Processor</tt> instance
+     * @return a new <tt>Processor</tt> instance which is to be used to play
+     * back the media provided by the specified <tt>dataSource</tt> or
+     * <tt>null</tt> if the specified <tt>dataSource</tt> is to not be played
+     * back
+     * @throws Exception if an exception is thrown by
+     * {@link DataSource#connect()},
+     * {@link Manager#createProcessor(DataSource)}, or
+     * {@link DataSource#disconnect()}
+     */
+    protected Processor createPlayer(DataSource dataSource)
+        throws Exception
+    {
+        Processor player = null;
+
+        // A Player is documented to be created on a connected DataSource.
+        dataSource.connect();
+        try
+        {
+            player = Manager.createProcessor(dataSource);
+        }
+        finally
+        {
+            if (player == null)
+                dataSource.disconnect();
+        }
+        return player;
+    }
+
     /**
      * Initializes a new <tt>Renderer</tt> instance which is to play back media
-     * on this <tt>MediaDevice</tt>.
+     * on this <tt>MediaDevice</tt>. Allows extenders to initialize a specific
+     * <tt>Renderer</tt> instance. The implementation of
+     * <tt>AbstractMediaDevice</tt> returns <tt>null</tt> which means that it is
+     * left to FMJ to choose a suitable <tt>Renderer</tt> irrespective of this
+     * <tt>MediaDevice</tt>.
      *
      * @return a new <tt>Renderer</tt> instance which is to play back media on
      * this <tt>MediaDevice</tt> or <tt>null</tt> if a suitable
      * <tt>Renderer</tt> is to be chosen irrespective of this
      * <tt>MediaDevice</tt>
      */
-    public abstract Renderer createRenderer();
+    protected Renderer createRenderer()
+    {
+        return null;
+    }
 
     /**
      * Creates a new <tt>MediaDeviceSession</tt> instance which is to represent

src/org/jitsi/impl/neomedia/device/AudioMediaDeviceImpl.java

@@ -191,16 +191,18 @@ protected void connect(
     }
 
     /**
-     * Initializes a new <tt>Renderer</tt> instance which is to play back media
-     * on this <tt>MediaDevice</tt>.
+     * {@inheritDoc}
      *
-     * @return a new <tt>Renderer</tt> instance which is to play back media on
-     * this <tt>MediaDevice</tt> or <tt>null</tt> if a suitable
-     * <tt>Renderer</tt> is to be chosen irrespective of this
-     * <tt>MediaDevice</tt>
+     * Tries to delegate the initialization of a new <tt>Renderer</tt> instance
+     * to the <tt>AudioSystem</tt> which provides the <tt>CaptureDevice</tt> of
+     * this instance. This way both the capture and the playback are given a
+     * chance to happen within the same <tt>AudioSystem</tt>. If the discovery
+     * of the delegate fails, the implementation of <tt>MediaDeviceImpl</tt> is
+     * executed and it currently leaves it to FMJ to choose a <tt>Renderer</tt>
+     * irrespective of this <tt>MediaDevice</tt>.
      */
     @Override
-    public Renderer createRenderer()
+    protected Renderer createRenderer()
     {
         Renderer renderer = null;
 

src/org/jitsi/impl/neomedia/device/AudioMixerMediaDevice.java

@@ -205,15 +205,28 @@ public AudioMixingPushBufferDataSource createOutputDataSource()
     }
 
     /**
-     * Initializes a new <tt>Renderer</tt> instance which is to play back media
-     * on this <tt>MediaDevice</tt>.
+     * {@inheritDoc}
      *
-     * @return a new <tt>Renderer</tt> instance which is to play back media on
-     * this <tt>MediaDevice</tt> or <tt>null</tt> if a suitable
-     * <tt>Renderer</tt> is to be chosen irrespective of this
-     * <tt>MediaDevice</tt>
+     * Delegates to the {@link AbstractMediaDevice#createPlayer(DataSource)}
+     * implementation of the <tt>MediaDevice</tt> on which this instance enables
+     * mixing i.e. {@link #getWrappedDevice()}.
      */
-    public Renderer createRenderer()
+    @Override
+    protected Processor createPlayer(DataSource dataSource)
+        throws Exception
+    {
+        return device.createPlayer(dataSource);
+    }
+
+    /**
+     * {@inheritDoc}
+     *
+     * Delegates to the {@link AbstractMediaDevice#createRenderer()}
+     * implementation of the <tt>MediaDevice</tt> on which this instance enables
+     * mixing i.e. {@link #getWrappedDevice()}.
+     */
+    @Override
+    protected Renderer createRenderer()
     {
         return device.createRenderer();
     }
@@ -650,6 +663,20 @@ protected DataSource createCaptureDevice()
             return getAudioMixer().getLocalOutputDataSource();
         }
 
+        /**
+         * {@inheritDoc}
+         */
+        @Override
+        protected Player createPlayer(DataSource dataSource)
+        {
+            /*
+             * TODO AudioMixerMediaDevice wraps a MediaDevice so
+             * AudioMixerMediaDeviceSession should wrap a MediaDeviceSession of
+             * that same wrapped MediaDevice.
+             */
+            return super.createPlayer(dataSource);
+        }
+
         /**
          * Sets <tt>listener</tt> as the list of listeners that will receive
          * notifications of audio level event changes in the data arriving from

src/org/jitsi/impl/neomedia/device/MediaDeviceImpl.java

@@ -167,20 +167,6 @@ protected DataSource createOutputDataSource()
                 : null;
     }
 
-    /**
-     * Initializes a new <tt>Renderer</tt> instance which is to play back media
-     * on this <tt>MediaDevice</tt>.
-     *
-     * @return a new <tt>Renderer</tt> instance which is to play back media on
-     * this <tt>MediaDevice</tt> or <tt>null</tt> if a suitable
-     * <tt>Renderer</tt> is to be chosen irrespective of this
-     * <tt>MediaDevice</tt>
-     */
-    public Renderer createRenderer()
-    {
-        return null;
-    }
-
     /**
      * Creates a new <tt>CaptureDevice</tt> which traces calls to a specific
      * <tt>CaptureDevice</tt> for debugging purposes.

src/org/jitsi/impl/neomedia/device/MediaDeviceSession.java

@@ -430,36 +430,13 @@ protected Player createPlayer(DataSource dataSource)
         Processor player = null;
         Throwable exception = null;
 
-        // A Player is documented to be created on a connected DataSource.
         try
         {
-            dataSource.connect();
+            player = getDevice().createPlayer(dataSource);
         }
-        catch (IOException ioex)
+        catch (Exception ex)
         {
-            // TODO
-            exception = ioex;
-        }
-        if (exception != null)
-        {
-            logger.error(
-                    "Failed to connect to "
-                        + MediaStreamImpl.toString(dataSource),
-                    exception);
-            return player;
-        }
-
-        try
-        {
-            player = Manager.createProcessor(dataSource);
-        }
-        catch (IOException ioe)
-        {
-            exception = ioe;
-        }
-        catch (NoPlayerException npe)
-        {
-            exception = npe;
+            exception = ex;
         }
         if (exception != null)
         {
@@ -468,7 +445,7 @@ protected Player createPlayer(DataSource dataSource)
                         + MediaStreamImpl.toString(dataSource),
                     exception);
         }
-        else
+        else if (player != null)
         {
             /*
              * We cannot wait for the Player to get configured (e.g. with
@@ -477,6 +454,7 @@ protected Player createPlayer(DataSource dataSource)
              * media (e.g. abnormally stopped), it will leave us blocked.
              */
             if (playerControllerListener == null)
+            {
                 playerControllerListener = new ControllerListener()
                 {
 
@@ -495,20 +473,20 @@ public void controllerUpdate(ControllerEvent event)
                         playerControllerUpdate(event);
                     }
                 };
+            }
             player.addControllerListener(playerControllerListener);
 
             player.configure();
             if (logger.isTraceEnabled())
+            {
                 logger.trace(
                         "Created Player with hashCode "
                             + player.hashCode()
                             + " for "
                             + MediaStreamImpl.toString(dataSource));
+            }
         }
 
-        if (player == null)
-            dataSource.disconnect();
-
         return player;
     }
 
@@ -939,12 +917,13 @@ public DataSource getOutputDataSource()
         {
             outputDataSource = processor.getDataOutput();
             if (logger.isTraceEnabled() && (outputDataSource != null))
-                logger
-                    .trace(
+            {
+                logger.trace(
                         "Processor with hashCode "
                             + processor.hashCode()
                             + " provided "
                             + MediaStreamImpl.toString(outputDataSource));
+            }
 
             /*
              * Whoever wants the outputDataSource, they expect it to be started

src/org/jitsi/impl/neomedia/device/VideoTranslatorMediaDevice.java

@@ -123,20 +123,6 @@ protected synchronized DataSource createOutputDataSource()
                 : deviceSession.getOutputDataSource();
     }
 
-    /**
-     * Initializes a new <tt>Renderer</tt> instance which is to play back media
-     * on this <tt>MediaDevice</tt>.
-     *
-     * @return a new <tt>Renderer</tt> instance which is to play back media on
-     * this <tt>MediaDevice</tt> or <tt>null</tt> if a suitable
-     * <tt>Renderer</tt> is to be chosen irrespective of this
-     * <tt>MediaDevice</tt>
-     */
-    public Renderer createRenderer()
-    {
-        return null;
-    }
-
     /**
      * Creates a new <tt>MediaDeviceSession</tt> instance which is to represent
      * the use of this <tt>MediaDevice</tt> by a <tt>MediaStream</tt>.